Upon receiving subject study scores, a student with a raw 30 in Latin would be ecstatic about their scaled score of 46, while a Systems Engineering student picking up a raw 30 might be less thrilled about their scaled score of 24.
Many are under the impression that scaling is VCAA's way of determining which subjects are “worth” more, however they do use an algorithmic method to determine which studies scale up, down or remain the same. The exception to this is a bonus of up to 5 points to encourage language studies. It’s a different discussion entirely as to whether this algorithm is fair – it’s based on an assumption of general intelligence, or the idea that a “general mental ability” is transferable across different areas.
First of all, let's look at the purpose of scaling. Scaling is primarily to account for competition levels in different subjects – if the final score was your raw score, scores obtained in different years would not be standardised. It’s worth remembering that a study score is nothing more than a ranking: if you get a 30, you’re the exact middle rank, while a 40+ score puts you in the top 9% of students that year.
So, how does VCAA actually arrive at the scaled score numbers? Simply, students’ scores in all of their other subjects are used to calculate how to adjust raw scores. For example, let’s take that Systems Engineering student who got a raw 30. In 2017, the average study score across all the other subjects studied by Systems Engineering students was 24: therefore, the average study score, a 30, was adjusted to become a 24.
Some take scaling to mean that they shouldn’t pick subjects that scale down, but you should never let this stop you choosing subjects you love! As a student who received an ATAR above 99 with no Maths or Science subjects whatsoever (although choosing a language did help…), I was incredibly thankful for the people who encouraged me to pick subjects which complemented my interests.
Disclaimer: As I'm not affiliated with VCAA, only aiming to make their information more accessible, check out this site to find out exactly what they say about scaling: http://www.vtac.edu.au/results-offers/atar-explained/scaling.html